The invention relates to a vertical centrifuge, with a housing provided with a cover and with a centrifuge drum which is arranged to be rotatable in the housing and which comprises an upper feed opening and a lower discharge opening, while above the discharge opening is arranged a screen or shield, which is carried and can be displaced by means of a holding arrangement with a shaft arranged on the cover.
During the filing of the centrifuge drum with a material which is to be centrifuged and during the washing of the material, the lower discharge opening of the drum has to be covered by means of a screen or shield. This prevents the splashing material which is to be introduced or washed being able, through the discharge opening, to make the material which has already been treated and which is underneath the discharge opening once again wet or dirty. However, with the discharge of the treated material from the drum, the path between a blade or knife of a stripping device and the discharge opening has to be made free.
With one known vertical centrifuge, this is obtained by the fact that the shield covering the discharge opening is raised by displacement and rotation of a shaft of a holding arrangement and is pushed to one side. However, also in this position, the wall of the shield still always obstructs the material which is to be discharged during its passage from the knife of the stripping device to the discharge opening.